Ginger curse People with red hair may be more prone to developing a deadly form of skin cancer regardless of whether they spend time in the Sun or not, a study has found.

Not only is this group more vulnerable to the Sun's ultraviolet (UV) rays, but a study in mice has now shown that the pigment that gives hair a red hue may in itself have cancer-causing effects, according to the study published in the journal Nature.

"We studied melanoma formation in 'redheaded' mice and discovered that the red pigment had an ability to promote melanoma formation, even in the absence of ultraviolet radiation exposure," says co-author David Fisher, cancer centre director at Massachusetts General Hospital.

"This was a surprising result for us, because we expected that fair skinned people get melanoma due to weak protection from sunlight and ultraviolet radiation.

"However the results suggest that even without UV exposure, the red pigment may contribute to melanoma formation" by damaging healthy cells.

In lab studies using dark, red and albino mice, Fisher and a team discovered that melanoma occurred more frequently in the red mice than the other two groups, regardless of whether they were exposed to UV or not.

The study shows "that completely avoiding UV rays would not protect red-haired people from melanoma," United States cancer researchers Mizuho Fukunaga-Kalabis and Meenhard Herlyn writes in a comment carried by Nature.

About 132,000 cases of melanoma, the deadliest form of skin cancer, are diagnosed each year and two to three million non-melanoma cancers, according to the World Health Organisation, which says the numbers rise every year.

Fukunaga-Kalabis and Herlyn say the findings raise the question: what can be done beyond Sun protection to reduce melanoma risk in red-haired, fair-skinned people?

They say further research is needed into the drugs that may induce eumelanin production or boost cancer-protecting antioxidants.